Transient myeloproliferative disorder (TMD) is an exceptional cause of noninfectious neonatal pustules.1 It is indistinguishable from congenital leukemia; the main difference is its spontaneous remission. However, 20% of patients with TMD develop acute megakaryoblastic leukemia during the first 4 years. Transient myeloproliferative disorder affects up to 10% of patients with Down syndrome, who also have an increased risk of developing congenital leukemia.2 This disorder has also been described in 46,XX karyotype individuals with trisomy 21 mosaicism.3 Recent studies show that acquired mutations in the transcription factor GATA1, found initially in acute megakaryoblastic leukemia in patients with Down syndrome, also cause TMD. A second genetic hit is necessary to develop leukemia.2,4